Calendering machine



June 24, 1969 5, w. KESLER CALENDERING MACHINE Sheet Filed March 17, 1967 INVENTOR GEORGE W. KESLER ATTORNEYS.

G. W. KESLER CALENDERING MACHINE June 24, 1969 Sheet Filed March 17, 1967' FIG 2 GEORGE W. KESLER ATTORNEYS.

United States Patent 3,451,332 CALENDERING MACHINE George W. Kesler, Richmond, Va., assignor to The Inta- Roto Machine Company, Inc., Richmond, Va., a corporation of Virginia Filed Mar. 17, 1967, Ser. No. 624,049 Int. Cl. 1330b 3/06, 3/04; B2111 131/04 US. Cl. 100-162 11 Claims ABSTRACT OF THE DISCLOSURE A calendering machine employing a main roll and a pair of pressure applying rolls, all of substantial weight and all carried by a common frame. The pressure applying rolls are positioned on opposite sides of the main roll so that they maintain di'ametrical contact with the main roll regardless of variation in the diameter thereof, and are connected together so that the pressure-exerting means does not transmit stress to the common frame, and the pressure applying rolls counterbalance each other in the event of failure of the pressureexerting means.

Background 0 the invention In the calendering and similar arts which involve the use of relatively heavy rolls for squeezing a web or sheet material, the supporting framework for the rolls is subjected to substantial stress due to the weight of the rolls alone. In prior art machines, the framework is also subjected to the stresses of reaction forces arising from the pressure-exerting means. As a consequence, the supporting framework must be designed to withstand both the static weight loads and the dynamic loads imposed by the pressure-exerting means. When it is realized that the force exerted by each pressure roll against the main roll may be very large, fifty tons for example, it will be appreciated that a frame of substantial mass normally is employed. Even so, the danger of frame distortion and consequent misalignment of parts incidental to operation is ever present.

The pressure rolls are journaled on individual arms which, in turn, are pivotally mounted on fixed axes on the frame. Desirably, the pressure rolls engage the calendering roll at diametrically opposite points, and the pressure rolls and their supporting levers are designed to diametrically engage a calendering roll of a given diameter. Thus, if the diameter of the calendering roll is varied, such as by grinding and refinishing the surface thereof, the engagement of the pressure rolls is not diametrical.

Finally, in the event of failure of the pressure-exerting means, the lower pressure roll will fall away from the calendering roll while the upper pressure roll will impose the static weight of both pressure rolls, their mounting levers and the pressureexerting means on the calendering roll because the pressure means usually interconnects the free ends of the mounting levers.

Summary of the invention It is of chief concern in the present invention effectively to eliminate teh imposition of frame stresses arising from the pressure-exerting means. This is accomplished first by mounting the pressure rolls in such a way that the resultants of their force on the main roll always act diametrically of the main roll irrespective of its diametrical dimension. The pressure-exerting means are connected between the carriage assemblies mounting the pressure rolls so that the forces exerted by the pressure-exerting means are reacted by and dissipated between such carriages without being transmitted to the frame.

In view of the fact that the carriage assemblies in any Too event must be capable of withstanding the forces involved, the above arrangement does not impose additional burden thereon, but only employs a more efficient and effective arrangement whereby the supporting frame is relieved of that additional burden traditionally placed upon it. Interconnecting mechanism between the carriage assemblies is effective in the event of failure of the pressure-exerting means, so that the weights of the two pressure rolls and their carriages are counterbalanced by each other to prevent shifting of either pressure roll in such event.

Brief description 09 the drawings FIG. 1 is a side elevational view of a calendering machine constructed according to this invention, and

FIG. 2 is a front elevation of the machine.

Detailed description With specific reference to the drawings, the supporting frame for the machine may include a pair of spaced upstanding pedestals 10 joined by lower horizontal cross frame members 12 and an upper cross frame member 14. As is evident in FIG. 1, the machine base may be secured to a suitable foundation as by log bolts 16. Intermediate saddle portions 18 of the pedestals and co operating bearing caps 20 serve to journal the opposite reduced ends or shaft portions 22 of an intermediate main or calendering roll 24. One end 26 of the main roll shaft is extended, as shown in FIG. 2, for receiving a gear or similar means for imparting rotation to the main roll from a suitable source of power.

Upper and lower pressure rolls 28, 28' are supported by movable carriage assemblies 30, 30 and the manner in which these carriage assemblies are mounted and their interconnection with force-exerting means 32, 32-, usually hydraulic jacks, constitute the essential feature of the present invention. The carriage assemblies are sub stantially identical and are quite similar to prior assemblies of this type in that each assembly includes a pair of parallel lever arms 34, 34' having one of their ends mounted on a cross shaft 36, 36, each having its opposite ends mounted in the pedestals 10. Bearing portions 38, 38 intermediate the length of the arms 34, 34' journal the shaft end portions 40, 40 of the pressure rolls 23, 28, and the free end portions of the arms are connected to the force-exerting means 32, 32' by pivots 42, 42'.

In the usual apparatus of this type, the pressure roll supporting arms are pivotally mounted on the same side of the main calendering roll and the force-exerting means is connected between the free ends of the arms on the opposite side of the main roll. Thus, the frame not only supports the static weight of the apparatus, but is also subject to the reactive stress between the arm pivots upon operation of the force-exerting means. Moreover, any change in diameter of the main roll will vary the opposed engagement of the pressure rolls from the ideal diametrical engagement.

According to the present invention, however, the pressure rolls, their supporting arms and force-exerting means are arranged symmetrically around the main roll, and the force-exerting means are connected between the free ends of one pair of arms and the supporting pivot of the other pair of arms so that the frame is subject to static weight only, and is free of other stresses. More specifically, the axes of the arm supporting shafts 36, 36 are arranged in a common plane with the axis of the main shaft 22, and are disposed at equal distances on the 0pposite sides thereof. Thus, the arms 34, 34' extend from their pivots 36, 36 in opposite directions relative to the main roll 24.

The axes of the pressure roll shafts 40, 40' equidistant from the axes of their respective 36, 36 and so that said roll shaft are spaced arm pivots axes are in a plane common to the axis of the main roll shaft 22 so that the pressure rolls 28, 28' engage the main roll 24 at diametrically opposite points. Moreover, diametrical engagement of the pressure rolls with the main roll will be maintained regardless of variation in diameter of the main roll because of the diametrical, coplanar disposition of the arm pivots 36, 36'.

The pressure-exerting means 32, 32 are shown as comprising hydraulic cylinders 44, 44' having rods 46, 46" extending therefrom. The cylinders have clevis ears 48, 48 respectively straddling the free ends of the respective arms 34, 34' and pinned thereto by the pivot pins 42, 42'. The piston rods 46, 46 are provided with clevis ends 50, 50' pivotally secured by pivot pins 52, 52' to ears 54, 54' integral with the respective roll carrier arms 34, 34' adjacent their bearings 56, 56' on the shafts 36, 36. By this arrangement, stresses created by operation of the pressure-exerting means is confined to the roll carrying arms, their supporting shafts and the pressure-exerting means. No stresses are transmitted to the supporting frame other than the static weight of the apparatus.

Any suitable means may be provided for controlling the action of the several hydraulic piston and cylinder assemblies 32, 32', it being appreciated that other and different mechanisms may be substituted therefore in order to urge the pressure rolls toward the main roll to squeeze the web therebetween. It also will be appreciated that conventional means may be provided to heat one or more of the rolls.

To protect the rolls 24, 28, 28' against damage in the event of failure of the hydraulic system, the cross shafts 36, 36 are provided with rigid levers 58, -8 at their opposite ends, and corresponding pairs of these levers are interconnected by tie rod 60 pivotally connected there to by pivot pins 62, 62. The levers 58, 58' extend in opposite directions relative to their respective arms 34, 34' so as to accommodate like movement of said arms relative to the main roll 24. Should the hydraulic system fail, the movement produced by the weight of the lower carriage and pressure roll will be transmitted through the levers 58' and tie rods 60 to the cross shaft 36 through the levers 58. This movement will be counterbalanced by the upward movement imposed upon the upper carriage and pressure roll, preventing the lower assembly from dropping.

In the symmetrical arrangement shown, it will be noted that a line joining the centers of the cross shafts 36, 36' intersects at a midway point the center line of the main roll 24 so that the two pressure rolls, being equidistantly spaced from their cross shafts, exert pressure under the influence of the means 32, 32 in diametrically opposed relation on the main roll 24 regardless of its diameter. Thus, forces on the main roll 24 due to the pressure means 32, 32 are in opposition and, assuming equal forces exerted by such means, will exactly cancel and no net resultant will be transferred to the frame pedestals. In the particular arrangement shown, this is due to the fact that the lines of action of the pressure means 32, 32 are parallel and the carriages 30, 30 are identical but reversed in position above and below the main roll 24.

In the machine specifically shown, the web W being calendered is fed in under the guide roll 64 and is wound back and forth over the several rolls 28, 24 and 28 to issue from beneath the lower pressure roll as shown.

Although certain specific embodiments of the invention have been shown and described, it is obvious that many modifications thereof are possible. The invention, therefore, is not to be restricted except insofar as is necessitated by the prior art and by the spirit of the appended claims.

What is claimed is: 1. A calendering or like machine comprising in combination,

a frame having a pair of upstanding supporting pedestals,

a main roll journaled between said pedestals,

a first carriage assembly including a pair of arms, means pivotally journaling said arms at one end and including a shaft extending between said pedestals,

a first pressure roll journaled by a shaft extending between said arm parallel to said main roll and adapted to swing with said first carriage assembly relative to said main roll into pressure exerting relation thereagainst,

a second carriage assembly including a second pair of arms, means pivotally journaling said arms at one end and including a shaft extending between said pedestals, the first pair of arms and the second pair of arms extending from their points of pivotal connection by said journaling means in opposite directions with respect to each other and the first and second pair of arms being disposed on diametrically opposite sides of said main roll, a second pressure roll journaled by a shaft extending between said second pair of arms parallel to said main roll and adapted to swing with said second carriage assembly relative to said main roll into pressure exerting relation to said main roll in diametrically opposed relation to the first pressure roll,

first power-operated pressure-exerting means connected between the free ends of said first pair of arms and the journaling means for said second pair of arms for moving the first pressure roll relative to said main roll, and

second power-operated pressure-exerting means connected between the free ends of said second pair of arms and the journaling means for said first pair of arms for moving the second pressure roll relative to said main roll,

the lines of action of said first and second pressureexerting means being substantially parallel and through said carriage assemblies and their journaling means so that the reaction forces of said first and second pressure-exerting means are not transmitted to said frame.

2. A calendering or like machine comprising in combination,

a frame having a pair of upstanding supporting pedestals,

a main roll journaled between said pedestals,

a first carriage assembly including a pair of arms pivotally supported at one end by a shaft journaled between said pedestals, a first pressure roll journaled between said arms parallel to said main roll and adapted to swing with said first carriage assembly toward said main roll into pressure-exerting relation thereagainst,

a second carriage assembly including a second pair of arms pivotally supported at one end by a shaft journaled between said pedestals, the first pair of arms and the second pair of arms extending from their points of pivotal connection in opposite directions with respect to each other and the first and second pair of arms being disposed on diametrically opposite sides of said main roll, a second pressure roll journaled between said second pair of arms parallel to said main roll and adapted to swing with said second carriage assembly toward said main roll into pressure-exerting relation to said main roll in dialtlmetrically opposed relation to the first pressure ro first pressure-exerting means connected between the free ends of said first pair of arms and the journaled ends of said second pair of arms for moving the first pressure roll toward said main roll, and

second pressure-exerting means connected between the free ends of said second pair of arms and the journaled ends of said first pair of arms for moving the second pressure roll toward said main roll,

the lines of action of said first and second pressureexerting means being substantially parallel so that the reaction forces of said first and second pressureexerting means are not transmitted to said frame,

the axes of said arm supporting shafts and said main roll being coplanar with the main roll axis equidistant between said shaft axes.

3. A machine as defined in claim 2 wherein the axes of said main and pressure rolls are always coplanar with the main roll axis equidistant between said pressure roll axes.

4. A machine as defined in claim 2 including tie rod means comprising,

lever means fixed on said arm supporting shafts, and

a tie rod assembly pivotally connected between said lever means,

said lever means extending from their respective shafts in opposite directions relative to their respective pair of arms. 5. In a calendering or like machine, in combination, a supporting frame, a main roll journaled in said frame, a pair of pressure rolls parallel to said main roll, carriage means respectively swingably mounting said pressure rolls on said frame for movement into pressure-exerting relation against said main roll, and

means connected with said carriage means for moving said pressure rolls relative to said main roll,

said carriage means having pivotal axes coplanar with the axis of said main roll and said pressure rolls having axes equispaced from their carriage means pivot axes so that said pressure roll axes are always coplanar with said main roll axis and said pressure rolls always engage exact diametrically opposed portions of said main roll regardless of variations in main roll diameter.

6. A machine according to claim 5 wherein said carriage moving means is connected directly between said respective carriage means thereby precluding the transmittal of pressure stresses to said frame.

7. In the machine according to claim 6 including means interconnecting said carriage means for counterbalancing the weight of one pressure roll with the other pressure roll.

8. A machine as defined in claim 1 wherein the axes of said journaling means shafts and said main roll are coplanar with the main roll axis equidistant between said shaft axes.

9. A machine as defined in claim 8i wherein the axes of said main and pressure rolls are always coplanar with the main roll axis equisdistant between said pressure roll axes.

10. A machine as defined in claim 1 including tie rod means interconnecting said first and second carriage assembles whereby the weights thereof are counterbalanced through said tie rod means.

11. A machine is defined in claim 10 wherein said tie rod means comprises,

lever means fixed relative to said carriage assemblies and extending radially of said journaling means shafts, and

a tie rod assembly pivotally connected between said lever means,

said lever means extending from their respective shafts in opposite directions relative to their respective pair of arms. 

